 var test = function test(){
    var containerEle = document.getElementsByClassName('container')[0];
containerEle.getElementsByClassName.width = '300px';
containerEle.innerHTML = "<div class=\"text\">" + 
                          "<span>用户名:</span><input/>"+
                          "</div>" +
                          "<div class=\"text\">"+
                          "<span>密码：</span><input/> class=password>" +
                          "</div>"
}
console.log(test);
